It said the big decrease shows that not only has the death rate from cancer been reversed, but it has been reversed so much that fewer people are dying, even though the population of elderly people, who are most susceptible to cancer, is growing.

The American Cancer Society projected there will be 559,650 deaths from cancer in 2007. "The Society also predicts there will be 1,444,920 new cases of cancer in 2007; 766,860 among men and 678,060 among women," it said in a statement.

The society uses a different method to project and calculate deaths now, so the 2007 numbers cannot be compared directly with the 2004 numbers.

"Cancer death rates have been declining for a long time. The declines have now outpaced the growth and aging of the population," Elizabeth Ward, director of surveillance research for the American Cancer Society, said in a telephone interview.

She said a small decline seen in the previous report had grown considerably, showing the trend was real.

Decreases in smoking may be a major factor, Ward said.

"I think tobacco control has had a real impact. There is also the influence of early detection and screening and thirdly the influence of improvements in treatment," Ward said.

The biggest fall in deaths was seen in colorectal cancer, the second-leading cause of U.S. cancer deaths, which will affect 112,000 people in 2007 and kill 52,000.

"Colorectal cancer really stands out," Ward said.

"There was a drop in both men and women, both a drop in mortality rates and in cancer incidence." The death rate from colon cancer fell by 5.7% in 2003-2004 from the previous year.

Colonoscopy, recommended for everyone when they reach 50, may be making a difference, Ward said. "Early detection and screening probably do make a contribution," she said, adding that better treatments also were a factor.

Yet only 50% of Americans over 50 get the recommended screening.

"We need to continue to encourage colorectal cancer screening because if we are seeing this much progress at the current rate, we certainly could achieve more," Ward said.

The organization makes a yearly compilation of cancer deaths based on data from the Centers for Disease Control and Prevention, the National Cancer Institute, the North American Association of Central Cancer Registries, the U.S. Census Bureau, state and local health agencies, and thousands of cancer registries.

In 2004, 553,888 people died from cancer, compared to 556,902 in 2003. Fewer people died from the four leading cancers -- lung, breast, prostate, and colorectal cancer -- with the exception of lung cancer in women.

The five-year survival rate for all cancer patients between 1996 and 2002 was 66%, the group said. That compares to 51% between 1975 and 1977.

The four leading causes of cancer in the United States are:

-- Lung cancer, which will be detected in 213,000 people in 2007 and kill 160,000

-- Prostate cancer, which will be diagnosed in 218,000 men and kill 27,000

-- Breast cancer, which will be found in 180,510 men and women and kill 40,900

-- Colon cancer, which will be diagnosed in 112,000 people and kill 52,000.

The statistics do not include squamous and basal cell skin cancers, which affect a million people a year.

The full report is available on the Internet at http://www.cancer.org/statistics.

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